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So, this is a specific task that states:

We're given a rectangular conductive contour with known dimensions $a=5cm$ and $b=7.5cm$ like in the picture. At the moment, the distance between the contour and a very long wire conductor, with known current $I=2A$, is $c=2.5cm$. The resistance of rectangular contour is $R=2\Omega$. At one point, the contour starts moving to the right (staying in the plane of the picture at the same time) and stops when it moves the distance $b$. What's the total charge that travels through the contour from the beginning moment to when it stops moving?

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So, what I did first is stated that the magnetic field around the long wire conductor at some distance $r$ is: $$\oint_C\vec{B}d\vec{l}=\mu_0\sum_C I$$ $$\oint_C B\cdot dl\cdot \cos<(\vec{B},d\vec{l})=\mu_0\sum_C I$$ $$\oint_C Bdl=\mu_0I$$ $$B\cdot 2\pi r=\mu_0 I$$ $$B=\frac{\mu_0 I}{2\pi r}$$ Now the magnetic flux through the surface of the rectangle would be: $$\Phi=\int_S \vec{B}d\vec{S}=\int_S B\cdot dS\cdot cos<(\vec{B},d\vec{S})=\int_S B\cdot dS=$$ $$=\int_{c}^{c+b}\frac{\mu_0 I}{2\pi r}\cdot a\cdot dr=\frac{\mu_0 I a}{2\pi}\ln{\frac{c+b}{c}}$$ Now, what confuses me is that I don't know the exact time interval the contour traveled from the first to second position, nor do I understand if it's static or dynamic induction, or both that occur during the movement. I had the idea of calculating the electromagnetic induction that occurred during the movement, then calculating the current due to induction as: $$I_{ind}=\frac{e_{ind}}{R}$$ and then calculating the total charge that went through the contour as: $$Q=\int_{\Delta t}Idt$$ But for all of that I need the time interval in which the contour moved, or even the speed at which it moved, from which I could calculate the time.
Can this be solved in any other way?

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$\mathcal E = (-) \dfrac{d\Phi}{dt}$ and $I= \dfrac{\mathcal E}{R} \Rightarrow I = \dfrac 1 R \dfrac{d\Phi}{dt} = \dfrac {dQ}{dt}$

$\displaystyle\int_0^Q dQ = \dfrac 1 R \int^{\Phi_{\rm final}}_{\Phi_{\rm initial}}d\Phi$

This is a way of measuring changes in magnetic flux and hence magnetic field strength of a uniform field if you have a (search) coil and a charge measuring device like a ballistic galvanometer.
Here is a brief outline of such an arrangement.

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